Life Cycle Assessment of Inland Green Hydrogen Supply Chain Networks with Current Challenges and Future Prospects
Malik Sajawal Akhtar, Rofice Dickson, Jay Liu
Abstract
Large-scale energy storage and mobility infrastructures are imperative for meeting the current global energy demand. With hydrogen increasingly emerging as a potential energy carrier, the development of global hydrogen mobility infrastructures is essential to accelerate the transition to a hydrogen economy. In this work, a comprehensive cradle-to-gate life cycle assessment (LCA) was performed for seven hydrogen delivery pathways: compressed gas via pipeline (CGH2-PL), compressed gas via tube trailer (CGH2-TT), liquid hydrogen (LH2), liquid organic hydrogen carrier with natural gas as a heating source (LOHC), liquid ammonia (LNH3), liquid organic hydrogen carrier with hydrogen as a heating source (LOHC-Own), and the direct utilization of NH3 in direct ammonia fuel cell vehicle (LNH3-DAFCV). The LCA results showed that CGH2-PL is the most sustainable option among all the above mentioned pathways as it showed to have the lowest global warming potential (GWP) (1.57 kgCO2-eq/kgH2). On the contrary, delivery via LOHC had the worst results and would have the highest emissions (3.58 kgCO2-eq/kgH2). However, by partially utilizing the produced hydrogen to fulfill the heating requirements during dehydrogenation (LOHC-Own), approximately 35% of the GWP was reduced to 2.34 kgCO2-eq/kgH2. Likely, delivery via LNH3 also showed significant emissions (3.14 kgCO2-eq/kgH2) and remained the second worst candidate for hydrogen delivery. However, the direct utilization of NH3 in DAFCV showed promising results for GWP (1.62 kgCO2-eq/kgH2), making NH3 a likely candidate for future hydrogen and energy carriers.